Crustacean processing, and more particularly, crab processing, typically involves a washing procedure to remove foreign objects and debris from the outer shell of crab sections. The debris includes slubb, a build-up of slime which is picked up from the sea floor and appears to only occur in catch location with low water levels and leech eggs which are minuscule sized objects which become attached to the underside of the crab legs in densely packed configurations. Typically, the upper sides of the legs are substantially free of such debris. Further, the upper sides are characterized by a layer having a red colour, and it is economically important that this red layer be retained during processing. The undersides are typically white.
Currently, there are a variety of methods for removing such debris and processing the legs for the consumer market. One of the methods involves manually cleaning the crab sections by making use of a hand-held brush. Manual brushing is generally satisfactory and meets quality specifications. The problem is that this method is expensive and labour-intensive. It is estimated that approximately 40 workers are required to scrub 30,000 pounds of crab sections within a typical nine hour workshift.
A further method currently employed involves semi-automated high pressure spray wash systems. The procedure involves passing the crab sections along a perforated conveyor belt. The high pressure water (approximately 1,000 psi) is blasted through the conveyor belt from a nozzle system beneath the conveyor. This procedure is rife with limitations, including:
(1) a loss of product yield due to the high pressure stream impinging on exposed meat in a butchered cavity; PA1 (2) worker intervention to flip the crab sections over to facilitate access and cleaning both sides of the crab; PA1 (3) excessive water consumption; PA1 (4) power consumption; PA1 (5) significant maintenance costs for the equipment employed; and PA1 (6) removal of layer of red colouring from upper sides of crab legs. PA1 conveyor means for conveying a body portion of a crustacean having legs; PA1 cleaning means for cleaning the crustacean legs, the cleaning means cooperative with the conveyor means; PA1 cutting means for cutting cleaned legs from the body portion; and PA1 means for removing the body portion remaining on the conveyor means subsequent to cutting. PA1 an endless loop conveyor of individual hooks in spaced relation for receiving the legs and a body portion; PA1 drive means for driving the loop, PA1 a cleaning station for receiving and cleaning the legs, the cleaning station including at least a pair of counter rotatable brushes for scrubbing the legs and simultaneously applying tension to the legs during rotation of the brushes; PA1 a cutting member for cutting the legs from the body portion; and PA1 at least one rotatable member for removing body portions remaining subsequent to a cutting operation. PA1 conveying, with a conveyor, the crustacean legs into contact with cleaning means: PA1 removing surface debris from the legs with the cleaning means; PA1 applying tension to the legs simultaneously during cleaning; and PA1 cutting the legs under tension to separate the legs from the body portion.
A further method for processing the crab sections includes manually sawing the crab legs. This method is, as well, affected by limitations such as significant product yield loss and significant labour intervention for positioning the crab for the sawing operation.
In view of the limitations currently being experienced in this art, there exists a need for an automated arrangement for processing the crab or other crustacean sections which can be more efficient and less expensive in terms of financial commitment and labour requirements. The present invention alleviates the limitations in the prior art and accordingly, one object of the present invention is to provide a highly efficient processing apparatus and a method of employing the apparatus.
In one aspect of one embodiment of the present invention, there is provided an automated apparatus for cleaning and separating the legs from a body portion of a crustacean, comprising:
The conveyor apparatus conveniently includes an endless loop of spaced apart hooks. The hooks are particularly useful to be positioned between the legs of the crab section at the underside of the body portion to which the legs are connected. This facilitates easy loading of the conveyor hooks by the operator. The hooks are preferably vertically disposed so that the legs are pendulant. It has also been found that by providing a conveyor such as that employed herein, cleaning of the conveyor is a much less difficult procedure than that which would be attributed to the spray bar conveyor system discussed herein previously.
The cleaning means may comprise a cleaning station that incorporates rotatable brushes for contact with the legs, with the conveyor being preferably inclined relative to the rotating brushes. It has been found that as the conveyor advances the crab sections forwardly and upwardly through the counter rotatable brushes of the cleaning station, more effective cleaning is achieved. This occurs as a result of the crab sections being advanced through a positive inclination along the brushes and therefore the legs are progressively scrubbed from directly adjacent the body portion to the tip of the legs prior to severing the legs from the body portion. As will be appreciated, this facilitates scrubbing and ensures that substantially all of the debris is removed from the legs prior to severance from the body. The result is a much more desirable product which is inherently more vendible.
The counter rotatable brushes may be independently driven or may have an indirect linkage to the conveyor. This will depend upon the size of the apparatus and other user requirements.
Turning to the brushes, the same preferably extend a substantial distance along the length of the conveyor and either side of the hooks of the conveyor such that the legs pass between the brushes as the crustaceans are conveyed. The spacing between the brushes and the brush stiffness will be such that the legs are somewhat tensioned as they are scrubbed to achieve effective scrubbing and further, to maximize the amount of leg length prior to the cutting operation. In this manner, a maximum amount of leg length results to increase the product yield and the economy of the method. As well, the downward tensioning assists the severing operation.
Excessive abrasion of the leg by the brushes can have the undesirable effect of removing an excessive amount of desirable red colouring layer from the upper sides of the crab leg sections. It is desirable to provide a means whereby the upper, red side experiences a more gently brushing or abrading than the lower white side. This may be accomplished by means of the counter-rotatable brushes comprising a first, harder brush positioned to scrub the white undersides and a second, softer brush positioned to scrub the delicate and less soiled upper sides of the legs.
In accordance with a further aspect of the present invention there is provided an automated apparatus for separating the legs from a body portion of a crustacean, comprising:
In order to manage the waste from the process, the apparatus includes a member for removing body portions that remain subsequent to a cutting operation. Advantageously, the individual hook portions of the conveyor facilitate simple removal of the body portion into a collecting bin or container. One embodiment of an apparatus for removing the body portions from the hooks of the conveyor comprises a rotatable brush for dislodging the body portion from the hooks. This form of the apparatus not only serves to dislodge the body portion, but also cleans the hooks of the conveyor for reloading.
In a further embodiment the counter rotatable brushes consist of first and second brushes, with the first brush having relatively soft bristles for contact with the red upper sides of the legs and the second brush having relatively stiff bristles for contact with the undersides of the crustacean legs. In use, the crustaceans are positioned on the conveyor such that the undersides of the legs substantially all face the first brush. Preferably, there is also provided anti-bias means positioned to directly or indirectly contact the legs as they pass between the brushes, to counterbalance the biassing effect of the first brush, which exerts as it contacts the legs a greater force against the legs than the second brush. The anti-bias means permits the legs to be positioned for generally even contact with the brushes as the brushes rotatably contact the legs.
The method of practising the present invention has been found to significantly reduce labour involvement and financial requirements and accordingly, in a further aspect of one embodiment of the present invention, there is provided a continuous method for separating crustacean legs from a portion body of the crustacean, comprising the steps of:
In a further embodiment, the crustaceans are positioned on the conveyor such that the upper sides of the legs substantially face in a first direction and the undersides face in a second direction. The cleaning means apply a more forceful cleaning operation to the undersides and a less forceful cleaning operation to the upper sides.